Method and device for testing a control unit

ABSTRACT

A method and a device for testing a control unit, in which sensor data are transmitted over a network connection to a real or simulated control unit, which data are calculated by a data processing system using simulation, in which the simulation of the sensor data takes place at least in part with at least one graphics processor of at least one graphics processor unit of the data processing system. The simulated sensor data are encoded in image data that are output via a visualization interface to a data conversion unit that simulates a visualization unit connected to the visualization interface. Via the data conversion unit the received image data are converted into packet data containing the sensor data through the network connection to the control unit.

This nonprovisional application claims priority under 35 U.S.C. §119(a)to European Patent Application No. EP 14169948.8, which was filed on May27, 2014, and which is herein incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for testing a control unit, inwhich sensor data are transmitted over a network connection to a real orsimulated control unit, which data are calculated via a data processingsystem using simulation. In addition, the invention also relates to asensor data simulator for simulating data of a sensor to test controlunits that process the simulated data, comprising a data processingsystem having at least one graphics processor unit.

2. Description of the Background Art

Methods and devices of this type are known in the prior art, especiallyin the field of automotive component supply. Such methods are known asHIL—hardware in the loop, or SIL—software in the loop. In these methods,either actual, technical control units or simulated control units aretested in that simulated sensor data are passed to them over a networkconnection as though the control units were installed in an actual motorvehicle and acquire environmental data detected by sensors or othermeasurement data, in particular in real time. Control units can thus befunctionally tested in this way with no need to perform actual testdrives, which is advantageous especially in the preproduction stage. Asimulated control unit can be, for example, a computer that in technicalterms behaves like an actual control unit because of software running onit.

It is also known in other fields to have computationally intensivesystem-internal tasks performed not only by the main processor of a dataprocessing system, but also to use the computing capacity of a graphicsprocessor of a graphics processor unit of the data processing system forthese tasks, since these processors are very powerful and in some casesare also present in a parallel architecture, and are not fully utilizedby their visualization tasks, and thus represent a hardware resourcethat can be used in an ancillary or even primary manner for computingtasks.

After calculation in this context, the data calculated by graphicsprocessors are transmitted from the memory of a graphics processor unitinto the main memory of the data processing system, which is the onlyplace they are further processed.

In the field of control unit testing using simulated environmentaland/or sensor data, in contrast, the graphics processors of the dataprocessing systems have not hitherto been used for simulation purposes,since there were no adequately fast transmission paths available toprovide the calculated data from a graphics processor unit to thecontrol units under test. Transmission of the calculated data from thegraphics processor unit first into the main memory of the dataprocessing system for the purpose of forwarding through networkconnections has hitherto cancelled out any speed advantage in thecalculation.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a methodand device with which tests for control units are made possible with theutilization of at least one graphics processor of at least one graphicsprocessor unit. In particular, even new, more computationally intensivesimulation applications should be made accessible in this way.

This object is attained in an embodiment according to the invention inwhich a simulation of the sensor data takes place at least in part withat least one graphics processor of at least one graphics processor unitof the data processing system, and the simulated sensor data are encodedin image data that are output via a visualization interface to a dataconversion unit, and via the data conversion unit the received imagedata are converted into packet data containing the sensor data, whichare transmitted in a packet-based manner, in particular according to theTCP/IP protocol, from the data conversion unit through the networkconnection to the control unit. The encoding of the simulated sensordata in image data to be output can be performed directly by the atleast one graphics processor unit, in particular by at least onegraphics processor of such a unit.

Thus, it is intended to exploit the speed advantage of at least onegraphics processor unit in the simulation of sensor data, which is tosay to calculate these data by at least one graphics processor, or, ifapplicable, multiple graphics processors working in parallel, in the atleast one graphics processor unit, and to now make these sensor dataaccessible to control units under test directly through a standardinterface for visualization to the outside world.

To this end, the invention provides for the image data that contain theencoded sensor data and that are output through the visualizationinterface to be converted by a data conversion unit into network data,or in other words network data packets containing the simulation data,which packets can be received by the control unit through its at leastone data input. For transmission over the network connection, it ispossible to use, e.g., the TCP/IP protocol, the UDP/IP protocol, or elseany other suitable protocol.

In an embodiment, the visualization interface used to output thesimulated sensor data can be an integral physical part of the at leastone graphics processor unit that simulates the sensor data. Internaltransmission paths upstream of transmission to the control unit are thusbypassed, and the simulation data are made directly available.

When multiple graphics processor units, if applicable, are used in thedata processing system, in contrast, each of the graphics processorunits does not need a separate visualization interface. If thesimulation is performed on only one graphics processor unit or with onlyone graphics processor, then it is advantageous for at least theparticular graphics processor unit performing the simulation to have aseparate visualization interface, preferably as a physically associatedhardware component that is structurally integrated.

In contrast, if multiple graphics processor units are employed for thesimulation, the invention can also provide for the image data in whichthe sensor data are encoded to be output only through a visualizationinterface that is associated with only one of the multiple graphicsprocessor units, in particular as a physically integral hardwarecomponent.

Here, the invention can additionally provide that the specificvisualization interface of the specific graphics processor unit that hasthe highest computational load of all graphics processor units used forthe simulation is used to output the image data. This graphics processorunit can also be used for encoding the sensor data in image data. Theother graphics processor units with lower computing loads that are usedin the simulation can transmit the simulation data they have calculatedthrough, e.g., internal transmission paths to the graphics processorunit performing the output. In this way, any transmission paths that maybe needed in parallel processing are limited to small quantities ofdata.

If the other graphics processor units used for the simulation haveseparate visualization interfaces, the invention can provide that theyare not used for simulation data output in accordance with theinvention. In contrast, these visualization interfaces can be used forother customary visualizations such as for monitor output.

Provision can be made according to an embodiment of the invention forthe data conversion unit to simulate a visualization unit, for example,a display, a monitor, a screen, etc., connected to the visualizationinterface, wherein this simulation takes place in particular withrespect to the graphics processor unit that is associated with thevisualization interface performing the output, in particular thegraphics processor unit of which the visualization interface is aphysical part, which is to say that in this embodiment the dataconversion unit passes itself off by technical means as, e.g., amonitor, in order to initiate output of the data.

An embodiment of this nature can be advantageous especially when the atleast one graphics processor unit used for the simulation itself checksa visualization interface that is associated therewith at leastlogically, and if applicable and preferably also physically, for thepresence of compatible connected visualization devices, and adapts theinterface and encoding of image data for a detected visualization unit,for example with regard to image resolution and/or frame rate.

Since the transmission rate would be sharply limited in the customaryvisualization mode with a frame rate of 50 or 60 Hz, the invention canprovide here that the encoding and output of the image data with sensordata encoded therein takes place with frame rates above these customarystandard frame rates that are used pursuant to applicable standards suchas, e.g., PAL or NTSC. For example, frame rates above 500 Hz, preferablyabove 1000 Hz, are chosen.

The invention can provide such a technically extreme frame rate becauseactual visualization of the image data containing the simulated sensordata does not take place, at least not through the visualizationinterface that according to the invention is used for purposes otherthan originally intended, and the extreme increase in the frame rateonly serves to increase the data transmission rate.

In this regard, it can be advantageous here for the data conversion unitto simulate, in particular to the graphics processor unit, a connectedvisualization unit that has the capability of visualizing image data atthis frame rate, in particular without this actually being the case. Thevisualization interface of the at least one graphics processor unit isthus used within the scope of the invention for purposes other thanoriginally intended.

A sensor data simulator as a device according to the invention can havea data conversion unit connected to a visualization interface (inparticular that is associated at least logically, and if applicable andpreferably also physically, with at least one graphics processor unit),in particular to a VGA, DVI, or HDMI port, wherein the data processingsystem, in particular the at least one graphics processor unit thereof,is configured to encode simulated sensor data in image data, and outputit through the visualization interface to the data conversion unit withwhich the received data can be converted into data packets containingthe simulation data, which data packets can be output to a networkinterface, in particular according to the TCP/IP standard.

A corresponding device according to an embodiment of the invention canbe composed of a data conversion unit comprising a receiving interfacefor connection to a visualization interface of a data processing systemthat is associated at least logically, and if applicable and preferablyalso physically, with a graphics processor unit and a transmittinginterface for the output of data packets of a packet-based networkprotocol, wherein the data conversion unit is configured to convertpayload data encoded in image data that can be received through thereceiving interface into network data packets containing the payloaddata that can be transmitted through the transmitting interface.

Here, the data conversion unit can also be further configured to holdavailable in internal storage operating parameters such as, e.g., theframe rate to be used, and to transmit them upon connection to avisualization interface of the data processing system that carries outthe simulation so that the system, in particular at least one graphicsprocessor unit thereof, configures itself accordingly.

It remains also advantageous in the application of the invention thatespecially computationally intensive real-time applications are madeavailable in the simulation by this means. For example, provision can bemade to simulate, using the data processing system or the at least onegraphics processor unit thereof, the sensor data from a LIDAR (LightDetection and Range) sensor, which are used in automotive applications,for example in self-steering vehicles. Even though the invention can beused in this application, it is not limited thereto.

Here the invention can provide that the data processing system, inparticular the at least one graphics processor unit thereof, is used tosimulate not only a 3D scene of a surrounding environment, but also theacquisition of measurement signals from this scene by a likewisesimulated LIDAR sensor that is positioned in the scene and that is movedin the simulated scene by a motor vehicle, for example. Control unitsfor LIDAR sensors can be tested in this way without the need to need toperform actual test drives and also without the actual existence of theLIDAR sensor.

The simulation of the sensor data can be accomplished via shaders, forexample, which can be implemented in software, in particular on the atleast one graphics processor unit, in particular are executed by atleast one graphics processor of the graphics processor unit. A shader isknown to one skilled in the art to be a program that tells a computerhow to draw something in a specific and unique way.

It is also possible to implement the functionality of a shader in ahardware circuit, for example as an application-specific integratedcircuit (ASIC).

A graphics processor unit can be a unit that is not only an integralpart of a data processing system, in particular of the motherboardthereof, but that can also alternatively be implemented as a separateunit that is removable from the data processing system, in particular asa plug-in card, wherein each graphics processor unit has at least onegraphics processor and can have at least one graphics memory of its own.The graphics processor unit can also have at least one visualizationinterface at least logically associated therewith that can serve tooutput image data to a visualization unit, e.g. a monitor. Preferably avisualization interface of a graphics processor unit is also directlyphysically associated with the graphics processor unit, which is to sayan integral hardware component of such a unit. At least in the case ofsuch a graphics processor unit, no additional data transmission pathsfor the simulated sensor data within the data processing system butoutside the graphics processor unit are then required.

The sensor data of a LIDAR sensor, which is to say, e.g., the distancesand reflection or brightness values and, if applicable, angularpositions, can then be encoded in the image data to be output throughthe visualization interface in this application. For example, thedistance values of the simulated LIDAR sensor can be encoded at theposition of the color values that otherwise are customarily present inimage data.

The conversion by the data conversion unit of the sensor data encoded inthe received image data can be a software-based process, for example,but in an embodiment it can be carried out by an integrated circuit thatis connected to the visualization interface, in particular to a DVI orHDMI port, wherein a logic circuit is programmed into the circuit. Sucha circuit can be implemented as an FPGA.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

DRAWING DESCRIPTION

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingwhich is given by way of illustration only, and thus, is not limitive ofthe present invention, and wherein the sole FIGURE illustrates an anexemplary embodiment of the invention in the application for LIDARsensors is described below with reference to the FIGURE.

DETAILED DESCRIPTION

FIG. 1 symbolically shows a data processing system 1 on which a 3Denvironment scene is simulated, here a scene of a driving motor vehicle.Also simulated is a LIDAR sensor carried by the motor vehicle thatsenses the environment around the vehicle by measurement in thesimulation. The calculation of the measurement values of the LIDARsensor in the simulation is performed on the basis of the simulatedenvironment data using at least one graphics processor of a graphicsprocessor unit 2 of the data processing system 1. The simulation of the3D environment scene can also be calculated on a different dataprocessing system than the simulation of the LIDAR sensor. Environmentdata and sensor data can also both be calculated/simulated with thegraphics processor unit 2. In the simulation of at least the sensordata, this graphics processor unit 2 can use a shader 3 that is usedonly to encode the simulated sensor data of the LIDAR in image data andto output it through a visualization interface 9, e.g., a DVI port,display port, HDMI port, etc. for example with a frame rate that isincreased greatly relative to the PAL or NTSC standard, e.g., 1000 Hz.An additional shader 4 can be operated in parallel in the graphicsprocessor unit 2 to carry out normal visualization of the simulatedscene, for example on a monitor 5. The shader 3 is a program that tellsthe computer how to draw an image that looks like it is produced by alidar sensor.

A data converter 6 is used, which is implemented by way of example hereas an FPGA (Field Programmable Gate Array), or can be an ASIC(application-specific integrated circuit), a microprocessor, etc., whichreceives the image data through its receiving interface 6 a and by whichthe sensor data received as image data are converted into networkpackets containing the sensor data, e.g., for an Ethernet networkconnection 7, through which the control unit 8 under test of a LIDARsensor receives these simulated data transmitted through thetransmitting interface 6 b.

Output of the simulated sensor data directly from the graphics processorunit 2 through its standard visualization interface 9 that is used for apurpose other than originally intended avoids internal transmissionpaths in the data processing system 1 so that even computationallyintensive real-time applications, such as the simulation of LIDAR sensordata here, are made available by the invention.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are to beincluded within the scope of the following claims.

What is claimed is:
 1. A method for testing a control unit, the methodcomprising: transmitting sensor data over a network connection to a realor simulated control unit; calculating the sensor data via a dataprocessing system using simulation, the simulation of the sensor datatakes place at least in part with at least one graphics processor of atleast one graphics processor unit of the data processing system;encoding the simulated sensor data in image data that are output via avisualization interface to a data converter that simulates avisualization unit connected to the visualization interface; convertingthe received image data via the data converter into packet datacontaining the sensor data; and transmitting the sensor data in apacket-based manner through the network connection to the control unit.2. The method according to claim 1, wherein the encoding of the sensordata in image data takes place with a frame rate greater than 500 Hz orgreater than 1000 Hz, and wherein the data conversion unit simulates avisualization unit that has the capability of visualizing image data atthis frame rate.
 3. The method according to claim 1, wherein the sensordata of a LIDAR sensor are simulated using the data processing systemvia a shader implemented in software on the basis of a 3D environmentscene that is likewise simulated by this data processing system or byanother data processing system.
 4. The method according to claim 1,wherein the distance values of a simulated LIDAR sensor are encoded inthe image data in place of color values.
 5. The method according toclaim 1, wherein the data converter is formed as an integrated circuitthat is connected to the visualization interface, and wherein theintegrated circuit comprises a logic circuit or is implemented as anFPGA.
 6. The method according to claim 1, wherein the sensor data istransmitted through the network according to a TCP/IP or UDP/IPprotocol.
 7. A sensor data simulator for simulating data of a sensor totest control units that process the simulated data, the simulatorcomprising a data processing system having at least one graphicsprocessor unit, the data processing system being configured tocalculate, using at least one graphics processor of at least onegraphics processor unit, at least a portion of the data to be simulatedand is connected to a visualization interface or to a DVI or HDMI portof a data converter, the data processing system being configured toencode simulated sensor data in image data and output the image datathrough the visualization interface to the data conversion unit withwhich the received data is converted into data packets containing thesimulation data, which data packets are output to a network interface.8. The sensor data simulator, wherein the data packets are output to anetwork interface according to a TCP/IP standard.
 9. A data conversionunit comprising: a receiving interface for connection to a visualizationinterface of a data processing system that is associated with a graphicsprocessor unit; and a transmitting interface for the output of datapackets of a packet-based network protocol; and a data converter thatconverts payload data encoded in image data that are received throughthe receiving interface into network data packets containing the payloaddata that are transmitted through the transmitting interface.